The present invention relates to a new and improved method of assembling a power steering control valve and, more specifically to a method of assembling a power steering control valve which is hydraulically centered.
A power steering control valve is hydraulically centered when equal fluid pressures are conducted to a power steering motor in response to equal clockwise and counterclockwise actuation of the power steering control valve.
A method of hydraulically centering a power steering control valve is disclosed in U.S. Pat. No. 5,230,273. In this patent, an outer valve member and follow-up member are connected with one end of a torsion bar. An inner valve member is positioned within the outer valve member. When a hydraulically centered condition has been determined for the power steering control valve, a hole is drilled in the inner valve member and an end portion of the torsion bar. A pin is inserted into this hole to interconnect the inner valve member and the torsion bar.
It has also been suggested that a hydraulically centered condition may be obtained for a power steering control valve by first interconnecting the follow-up member, torsion bar and inner valve member. An outer valve member is then moved relative to the inner valve member. When a hydraulically centered condition has been ascertained for the outer valve member, the follow-up member is pressed into the outer valve member. This method of assembling a power steering control valve is disclosed in U.S. patent application Ser. No. 08/496,766 filed Jun. 29, 1995 and entitled "Method and Device for Assembling a Servo Valve."